Wireless Roaming

[APGC]

Hi,

First, apologies if this has already been covered in a different post.

I have 4 RT-AC68U's, spread throughout a large property. I have 1 configured as a Router, the 3 other ones as Access Points. The router one is connected to WAN and assigns reserved IP addresses to the other 3 AP's based on DHCP reserved IP addresses linked to the MAC's of the AP's. The 3 AP's are connected to the master router through managed switches.

I have configured all devices with the same SSID for 2.4 and for 5Ghz. That is: no separate SSID for 2.4 or 5. I have configured all devices to use different radio channels, ensuring there is enough delta between the closest devices.

In theory, this should result in transparent roaming throughout the property. However, in practice, streaming and facetime are cut as I roam through the property and hop onto a different device.

What am I doing wrong? I have a hunch that maybe I should give separate SSID's to 2.4 and to 5 Ghz? Maybe the cutoff is when the client switches to a different frequency?

Hope I was clear enough, looking forward to suggestions.

Thank you
APGC

 

[elpibe10]

For transparent or seamless roaming, your AP must support it.

An example would be Ubiquiti's Zero-handoff roaming.

Personally, I'm using a bunch of their Unifi APs strategically placed throughout my house to do that.

 

[APGC]

Hi elpibe10,

Thank you for your input. I already invested in the Asus equipment, so I really hope there's a way to get them to roam. Are you implying that the Asus kit doesn't support Roaming? Or you just know that Unify does?

Regards,
APGC

 

[CaptainSTX]

Roaming is not part of the specification for WiFi so no SOHO routers include the feature.

The equipment mentioned in the previous post is really commercial equipment at a price that most SOHO users can afford to pay.

Some people claim they have seamless roaming but it is probably a result of the layout of their space and has little to do with the underlying technology.

The most common solution to your problem is to give each AP a distinctive SSID (Den, Upstairs, etc. ) and tell people that if they want the strongest/fastest connection take the time to connect to the nearest AP.

Not what you want, but that is how the technology at the SOHO works.

 

[Pericynthion]

The delay you're seeing is the AP & client renegotiating a connection every time it transitions to a new radio.

As per CaptainSTX's note, there is a standard (802.11r) which does fast base station switching by pre-caching some of the authentication, but I dont believe I know of any home router lines that support it.

There was some rumblings about support in DD-WRT firmwares, but I've personally never seen it / testing it.

Edit: Apple tries to be ready for it client side it seems.. http://support.apple.com/kb/HT5535

 

[elpibe10]

Hi elpibe10,

Thank you for your input. I already invested in the Asus equipment, so I really hope there's a way to get them to roam. Are you implying that the Asus kit doesn't support Roaming? Or you just know that Unify does?

Regards,
APGC

I know for sure the WiFi on Asus routers can't roam seamlessly.

Among the companies that manufacture APs with seamless-handover roaming, Ubiquiti is probably the most economical (especially for home users).

I've already been using it for over 3 months and the earlier beta firmware was quite bad (eg. refusing to connect a closer AP with stronger signal) but the latest ones (ver 3.1.6 and 3.1.7) have been great.

I do Facetime and VoIP calls with my business associates / clients very often and the ability to have seamless roaming is mandatory.

 

[TimothyM96]

I have been able to roam inbetween an AC66U and a AC68U no problem, but they weren't in AP mode.

 

[elpibe10]

I have been able to roam inbetween an AC66U and a AC68U no problem, but they weren't in AP mode.

Roaming and seamless roaming aren't the same.

Especially if switching between AP when you're on a Facetime or VoIP call. That split second AP change-over (on non-seamless roaming) will disconnect you from your call.

 

[TimothyM96]

Roaming and seamless roaming aren't the same.

Especially if switching between AP when you're on a Facetime or VoIP call. That split second AP change-over (on non-seamless roaming) will disconnect you from your call.

I tested a Facetime call and there were no drops until I started getting out of range of both.

 

[elpibe10]

I tested a Facetime call and there were no drops until I started getting out of range of both.

I'm afraid that's technically not possible.

Most likely you're connected to the same AP / Router throughout your entire call; or perhaps your 4G/LTE connection ?

Without seamless WiFi roaming, your call will definitely be disconnected the moment you switch from one AP/Router to another.

 

[TimothyM96]

I'm afraid that's technically not possible.

Most likely you're connected to the same AP / Router throughout your entire call; or perhaps your 4G/LTE connection ?

Without seamless WiFi roaming, your call will definitely be disconnected the moment you switch from one AP/Router to another.

It got a huge quality decrease, but as I started getting close to the other router it got better. Each router is at the end of the home, in the center of the home I have 2/3 bars so I know I'm still connected to the farthest from me. But I get to the kitchen, which is at the end, and my full bars come back since I'm about 10 ft area from the other repeater. During that few moments of it switching, it didn't drop. The quality did get bad for a for a second, but camera movements still went though.

Maybe you have something in your setup that isn't allowing you to do that, but I tried with two 5S's and it worked fine.

 

[elpibe10]

It got a huge quality decrease, but as I started getting close to the other router it got better. Each router is at the end of the home, in the center of the home I have 2/3 bars so I know I'm still connected to the farthest from me. But I get to the kitchen, which is at the end, and my full bars come back since I'm about 10 ft area from the other repeater. During that few moments of it switching, it didn't drop. The quality did get bad for a for a second, but camera movements still went though.

Maybe you have something in your setup that isn't allowing you to do that, but I tried with two 5S's and it worked fine.

It's technically not supposed to work but if it does, then I'm guessing Apple could have improved the buffering capability in the newer versions of Facetime which allowed it to stay 'alive' during the AP switch-over.

The last time I tried (many months back), it didn't work. Same thing with VoIP calls.

If seamless roaming works even on consumer routers and APs (which I know it doesn't), then I'm curious why businesses invest in tons of $ on Cisco's seamless roaming networking equipment

 

[jdabbs]

It's technically not supposed to work but if it does, then I'm guessing Apple could have improved the buffering capability in the newer versions of Facetime which allowed it to stay 'alive' during the AP switch-over.

The last time I tried (many months back), it didn't work. Same thing with VoIP calls.

If seamless roaming works even on consumer routers and APs (which I know it doesn't), then I'm curious why businesses invest in tons of $ on Cisco's seamless roaming networking equipment

To clarify/expand on this somewhat:

People are generally aware of the network name (SSID) and its use as a network identifier. From the wireless client's perspective, there is also another identifier: the BSSID. In the OP's scenario, each router/AP would have its own BSSID (and perhaps one for each band); it is up to the client to decide when it is appropriate to hop to a new network. It would be preferable for the client to hop over whenever a better alternative exists, but in practice, the client tends to cling to the existing network until it is no longer an option. This behavior is what thwarts a smooth transition.

802.11r was mentioned in an earlier post--the presence of this support would make no difference, as 802.11r is a solution to a different problem. The process of disassociating from the current network and joining another can be accomplished fairly quickly (but not always), provided there's no external authentication. With an authentication server in the picture, the delay to reauthenticate can be several seconds. 802.11r allows the device to rejoin without having to receive immediate approval from the authentication server. In the OP's case, these routers wouldn't talk with each other to share this information, so 802.11r support on the routers and client is meaningless.

I run a modest Cisco enterprise deployment. We don't use VoWLAN (helping users save money on their personal phone bill is fairly low on my list of priorities), but 802.11r would certainly help if roaming were an issue. 802.1k addresses load balancing, and 802.11r makes that feasible. There are other features, like automatically switching to a channel with less interference, or notifying me if an "evil twin" AP is detected.

 

[RMerlin]

Asus also recently added an option to force client disconnection if their RSSI drops below a pre-configured level.

It might not provide for a smooth connection hands off however, but it could help with roaming.

 

[starfall]

This is because of hardware acceleration on the ASUS routers dropping the connection when the source IP changes interface. I've tested this and confirm that after disabling hardware acceleration, roaming works quite well.

Asuswrt-Merlin - Custom firmware for RT-N16 - Roaming between access points

 

[Matthew Patrick]

Asus also recently added an option to force client disconnection if their RSSI drops below a pre-configured level.

It might not provide for a smooth connection hands off however, but it could help with roaming.

So even on AC88U still doesn't support the 802.11 R,K,V standards? That's too bad

 

[RMerlin]

So even on AC88U still doesn't support the 802.11 R,K,V standards? That's too bad

Support for these is very rare in the home market, they are usually restricted to the business market. That might be because it's tied to specific chipset platforms and Broadcom possibly can't support it.

 

[Matthew Patrick]

Support for these is very rare in the home market, they are usually restricted to the business market. That might be because it's tied to specific chipset platforms and Broadcom possibly can't support it.

So. I can't make a seamless roam between my 2.4 and 5ghz? Well that kinda sucks. Hahaha. Tho. Smartconnect does seems like a good idea but the fact it's forcing the channels to auto is a deal breaker for me..

 

[RMerlin]

So. I can't make a seamless roam between my 2.4 and 5ghz? Well that kinda sucks. Hahaha. Tho. Smartconnect does seems like a good idea but the fact it's forcing the channels to auto is a deal breaker for me..

Most technically advanced user will tell you that Smart Connect is mostly useless for them. It's just a gimmick for novice users who don't want to manually associate their clients to the best radio. It's not that hard really to connect your slow/long-distance clients to the 2.4 GHz SSID, and those in need of high performance to the 5 GHz band - it's the only way to ensure you get the desired results. Ultimately, how well a client react to being bumped between interfaces is up to each individual clients.

 

[Matthew Patrick]

Most technically advanced user will tell you that Smart Connect is mostly useless for them. It's just a gimmick for novice users who don't want to manually associate their clients to the best radio. It's not that hard really to connect your slow/long-distance clients to the 2.4 GHz SSID, and those in need of high performance to the 5 GHz band - it's the only way to ensure you get the desired results. Ultimately, how well a client react to being bumped between interfaces is up to each individual clients.

Hmm. Does the client register it as disconnected ? Like on a mobile phone for example. When smartconnect steer your device. Does it shows the connection as disconnected then reconnected on the phone? Or it's like seamless in your phone connection status?